Washing and like treatments of textile fibres and materials



A. F. PFEIL pril 7, 1970 WASHING AND LIKE TREATMENTS 0F TEXTILE FIBRESAND MATERIALS Filed April 4, 1966 5 Sheets-Sheet 1 bn m u 3 I I N? @IF rg a E 9 1 m N W M Q U A F. een.

A in 1, 1-970 WASHING AND LIKE TREATMENTS 0 F TEXTILE FIBRES ANDMATERIALS Filed April 4, 1966 5 Sheets-Sheet 2 Allan F Pf L/ fl jmmmfirApril 7, 1970 A. F. PFEIL 3,505,004

I WASHING AND LIKE TREATMENTS OF TEXTILE FIBRES AND MATERIALS FiledApril 4, 1966 5 Sheets-Sheet 5 ohm Allan F Pfei/ %-Jm/Wr data A. F.PFEIL April 7, 1970 WAS HING AND LIKE TREATMENTS OF TEXTILE FIBRES ANDMATERIALS 5 Sheets-Sheet Filed April 4, 1966 Allan F pfei/ WASHING ANDLIKE TREATMENTS OF TEXTILE FIBRES AND MATERIALS Filed April 4. 1966 A-F.PFEILI April 1, 1970 5 Sheets-Sheet 5 09% Allan FPfeH Jm/7Wg4- R R xx 8:Q & @Q

United States Patent Oflice 3,505,004 Patented Apr. 7, 1970 3,505,004WASHING AND LIKE TREATMENTS OF TEXTILE FIBRES AND MATERIALS AllanFrederick Pfeil, Deptford, London, England, as-

signor to J. Stone & Company (Deptford) Limited, Deptford, London,England Filed Apr. 4, 1966, Ser. No. 539,830 Claims priority,application Great Britain, Apr. 22, 1965,

,020/ 65 Int. Cl. D06l J/02 U.S. Cl. 8-137 11 Claims ABSTRACT OF THEDISCLOSURE A two-step cleaning process for textile materials in which asurfactant is applied with a high concentration and low energy initiallyand thereafter a surfactant is applied with a low concentration and highenergy.

This invention concerns improvements relating to the washing, cleansingor like treatment of textile fibres and materials and of made-up fabricsand cloths and more particularly to the laundering of soiled linenarticles, the rinsing or washing of textile fabrics, and the similartreatment of textile fibres, such as the scouring of wool, and toimproved apparatus for carrying out these processes and treatments. Allsuch treatments will be referredto hereinafter as the washing of amaterial, but it is to be understood that the invention is applicablealso to the aforesaid other treatments of a like nature, which may becommonly known by various names in the particular trades or industriesconcerned.

These treatments are generally intended to remove impurities or soiling,whether naturally occurring or artificially introduced by use or by aprior treatment. Typically the material is treated by washing liquorswhich contain cleansing chemicals, by rinsing liquors to remove theresulting soiled liquors, and by finishing chemicals such as starch,bleaches, sours, blues and fluorescing materials. The washing liquor maybe water or an aqueous solution or .may be a solvent. Cleansingchemicals in general use may be conveniently classified, according totheir principal specific action, as:

(a) Surface-active agents (hereinafter referred to as washing agents)such as soaps and detergents whose principal action is a physical one bymodifying the surface tension and also, by interaction, causing soil tocome free from internal and external surfaces of individual fibres andto be held in suspension.

(b) Chemical agents such as alkaiis or acids (sours) whose principalaction is a chemical one by combination with or neutralisation ofimpurities or soil in the material or liquor. In some cases, fattysoiling is saponified by the chemical action of alkalis, therebyproducing fatty acids which in turn act in some ways like soaps ordetergents, modifying the surface tension. Nevertheless, the principalaction is a chemical one.

Suspension agents such as polyvinyl pyrrolidone, sodium carboxymethylcellulose or sodium carboxymethyl starch, whose principal action is toprevent redeposition of particles or chemicals, already removed from thetreated materials, by causing them to remain in suspension.

For a better understanding of the invention, it is necessary todistinguish between the washing agents (a) and chemical agents (b). Thespeed of action and efficiency of the agents (a) is related not only tothe amount of the washing agent used, but also to its concentration. Inthe case of the agents (b), although high concentration increase thespeed of reaction, they may also produce unacceptable chemical damage tothe fibres, so that they cannot be used.

Historically, washing processes have depended on lengthy soaking inwashing liquors combined with agitation or mechanical manipulation andthese features are still found in almost all processes, whetherindustrial or domestic. A variety of methods have been suggested in thepast for laundering and other treatments, such as the scouring of rawwool, by which the purposes of timeconsuming soaking processes were tobe more quickly achieved by energy-applying methods such as the actionof sprays or jets or by intensive agitation.

For these methods, the washing liquor is usually a weak aqueous solutionof a surface-active washing agent such as soap or detergent incombination with an alkali or alone. It is common to these methods thatthe washing agent is dissolved in a large volume of water and cannottherefore be quickly varied in amounts to meet the requirements ofvarying degrees or types of soiling. It is also common that the sprayingaction or agitation produces aeration of the washing liquor if the agentis present in sufficient concentration. This aeration leads todifiiculties with pumping equipment and decreases the intensity of theenergy which can be applied effectively to the material. It alsoproduces foam or lather which results in further difficulties, forinstance in controlling the depth of liquor in wash tanks.

It has been found that where the washing agent used is an orthodoxhigh-titre soap, washing liquors containing more than 0.01 part ofactive fatty-acid soap in every parts by weight of liquor may producesuch difiiculties when subjected to the higher energy levels necessaryfor high-speed processes. On the other hand, washing liquors mustcontain more than 0.025 part of soap in 100 parts of liquor if theaddition of the agent is to produce a significant improvement in thewashing effect. It follows that, with increasing concentration, ahigh-energy washing liquor will foam before it will wash. It is anobject of the invention to overcome this inherent contradiction, whichapplies similary to other washing agents.

The use of non-foaming or anti-foaming washing agents in the liquor hasbeen suggested. However, in many processes, the washing effect dependson a change of surface tension and this change itself makes the liquorliable to foaming and aeration. Thus, any liquor containing asufficiently high concentration of agent to give elfective washing willalso have an increased tendency to foaming and aeration as compared withsoft water or with alkali dissolved in soft water. Whereas anti-foamingagents may be effective at the low energy levels of slow processes, atthe high energy levels necessary for high-speed washing processes, theeffect achieved is not sufficient to counteract the aeration unless theagents, which are comparatively expensive, are added in uneconomicalquantities. Accordingly the invention seeks to eliminate the need to usesuch special agents.

A further object of the invention is to provide for the introduction ofthe washing agent into the material in a controlled manner and inproportions that can be easily varied, so that further economies in thisrespect can be achieved.

According to one feature of the invention in a process for washing,cleansing or like treatment of the kind set forth, the material issubjected to the action of a surfaceactive washing agent applied to itin one stage of the process and to the separate action of a washingliquor applied energetically in another stage thereof. Thesurface-active washing agent can thus be applied with a low level ofenergy and a high concentration of active substance, whereas the washingliquor is applied with a high level of energy and a low concentration ofactive substance.

Advantageously, the ratio of the level of energy with which the washingliquor is applied to that with which the surface-active washing agent isapplied is not less than 100 to 1, measured in units of energy per unitof area of material processed, while the ratio of the concentration ofsurface-active substance in the washing agent to that of activesubstance in the washing liquor is greater than 50 to 1.

Thus the energy with which the surface-active washing agent is appliedto the material should preferably be less than 1.85 X joules per squarecm., whereas that with which the material is subjected to the action ofthe washing liquor should be more than 200 10 joules per square cm. Theactive substance contained in the washing agent should have a detergencyeffect equivalent to an aqueous solution of orthodox high-titre soap ina concentration of between 0.25 and 5.0 parts by weight of activefatty-acid soap in 100 parts of solution, whereas the active substancein the washing liquor should have a detergency elfect equivalent to sucha solution of less than 0.01, and preferably less than 0005 part byweight in 100 parts of solution. In this manner, difficulties caused byfoaming and aeration of the wash liquor can be avoided and economies canbe achieved in the energy and power consumed, while the inherentcontradiction referred to above can be overcome. Finally, the washingagent can be quickly controlled quantitatively or qualitatively to suitdifierent degrees of soiling.

In a typical orthodox laundry process for washing 45 kgs. of mediumsoiled bed linen, a total of 630 litres of water is used in threewashing stages, a total of 475 grns. of high-titre soap being added,which represents an average concentration of 0.075 part per 100 parts ofliquor by weight. The stage with the highest concentration has 370 grns.of soap added to 300 litres, i.e. 0.123% by weight.

For an equivalent wash, employing the process of the invention, thewashing agent can be used at a concentration of 0.5 part of high-titresoap per 100 parts of solution. The concentration of active washingagent in the washing liquor, which represents only untilised agentcarried through into the liquor in the material being processed, isnegligible, being less than 0.003 part of agent per 100 parts of liquorby weight. A saving of about 10% in the total soap used as compared withthe orthodox process is achieved.

For orthodox laundry processes, recommended average concentration ofwashing agent for different degrees of soiling (Technology of Washing,published by B.L.R.A., 2nd edition, 1961) vary from 0.03% to 0.12% andmaximum concentrations from 0.0475% to 0.17% by weight. For the processof the present invention, for a similar range of soiling, the washingagent is preferably used at concentrations of from 0.5 to 2.5%, i.e.from 10 to times those used in equivalent orthodox processes. In spiteof the much higher concentration, however, the amount of agent utilisedis of the same order as or, in many cases, even less than in theorthodox processes.

In a typical commercial process for scouring raw wool, for every 45 kgs.of material, 130 gms. of washing agent and 450 litres of water are used,which represents an average concentration of 0.017 part of agent per 100parts of solution. For an equivalent wash, employing the process of thepresent invention, the agent can be used at a concentration of 0.6%,which is times greater than that of the aforesaid process.

In the process of the invention, the application of the washing agent ina concentration many times greater than that generally used heretoforeenhances its cfiicacy. Also, the period required for the agent to rollup or remove grease and dirt from individual fibres and to bring theminto suspension is largely due to the time required for the wholearticle to become wetted out and not to the time required for theremoval of action itself. By bringing the agent into intimate contactwith the material, the former time can be greatly reduced. The inventionaccordingly seeks to apply the surface-active agent to the material inno more than the amount and concentration required, to bring the saidagent into intimate contact with the fibres of the material with use ofa small amount of energy or agitation and to remove any surplus agentbefore subjecting the material to the action of high-energy jets orsprays of washing liquor or to the action of intense agitation.

The amount of energy actually required to deliver an agent to thesurface of the material is dependent on the method employed. Forexample, if the material is passed through a trough or tank, the energyrequired is negligible. Other known methods, such as those commonly usedfor delivering printing inks or dyes, also involve negligible energy.Preferably, in the process of the invention, the surface-active washingagent is applied to the material in such a manner that there is neithersubstantial dissipation of energy nor substantial agitation.

In some cases, as where a surface-active washing agent is available, inan appropriate concentration, under pressure through a pipeline, it maybe convenient to apply the agent by means of sprays. In such cases, theagent may be sprayed at a very low pressure just sufficient to obtaineven distribution of the agent across the material, but not so high thatthe agent is subjected to aeration or strikes the material withsubstantial energy. It has been found that commercially available sprayscan give effective distribution of the agent when a pressure of lessthan 2 kg. f. per sq. cm. is employed and that, by using wideanglesprays, the agent can be applied to the material with relativevelocities of less than 30 metres per minute, giving a resultant energyeffect of less than 1.85 X10 joules per sq. cm. This energy figure maybe compared with typical conditions for the washing liquor in previouslyproposed high-speed washing processes, where it has been found thatrelative velocities of at least 45 metres per min. and a far higherenergy effect may be necessary to obtain satisfactory results.

The washing liquor and rinsing liquor may also be applied by spraying,the former at a pressure of, say, more than 6 kg. f. per sq. cm. fromjets at not more than 15 cms. from the surface of the material and thelatter at a pressure of, say, not more than 3.5 kg. f. per sq. cm. Inconnection with any of the sprays, provision may be made forquantitative control by variation of the pressure.

In calculating the aforesaid energy effect Be, the following expressionhas been used.

bVm Where:

F=fiow of liquid in litres per min.

Vr=relative velocity of liquid with respect to the material in metresper minute.

b=breadth of material in cms.

Vm=velocity of material in metres per min.

Applying this to an example of the invention, in which the washing agentis applied at 4.6 litres per min. over a breadth of cms. at an angle of45 in the direction of travel of the material moving at 30 metres permin.:

joules per square em.

Ee=1.3 l0 joules per sq. cm.

If the washing liquor is applied in two stages at 350 litres per min.over a breadth of 100 cms. perpendicular to the travel of the materialmoving at 30 metres per min.:

Ee=595 10 joules per sq. cm.

within it the correct amount of washing agent before it is presented tothe action of the washing liquor.

It has ben found that when a surface-active washing agent is broughtinto contact with soiled material and soil is removed from the surfacesof the fibres, the proportion of the agent utilised in such removalbecomes inactive. It has also been found that, when subjected toagitation, this inactive agent is less liable to produce foam oraeration than is the unalfected, active, or free agent. In the processof the invention, the washing agent applied can be substantially allutilised and become inactive within the material. As the amount of freeagent is reduced to a minimum, the concentratian of agent in the liquorcan be prevented from reaching a level at which aeration or foamingoccurs, but without reducing the effectiveness of the process.

The invention thus provides a process in which material is treated byapplying a concentrated washing agent evenly over the whole of thematerial, but using only a low level of energy, causing the agent to bebrought into intimate contact with the fibres of the material, removingany excess agent in such a manner that an amount of agent remains in thematerial suflicient to act upon grease and soil in the material, but notsufiicient to leave excess active agent which would tend to causeaeration and foaming in later stages of the process, subjecting thematerial to the action of a washing liquor having no significanttendency to aerate or foam at a high level of energy produced byagitation or by application of the liquor under pressure through jets orsprays, and removing excess liquor together with inactive washing agentand suspended grease and soil. The material may then be passed from thewashing stage directly to a stage or stages in which the agent andliquor remaining in the material are removed by rinsing. Alternatively,the material may be passed from a first washing stage as described aboveto one or more further such washing stages and then to one or morerinsing stages.

Where two or more stages are provided, the amount or concentration andthe type of washing agent applied, or the proportions of combinedwashing agents applied may be made ditferent as between one stage andanother in order to deal with a wide range of types and degrees ofsoiling. Also, the washing liquor used may be different in type,concentration or temperature as between one stage and another.

The range of commercially available substances which can be used assurface-active washing agents is wide and includes low-titre andhigh-titre soaps, castor oil and other natural oil-based soaps andsynthetic detergents, as well as proprietary formulations. It is anadvantage of the invention that the use of more expensive agents is notessential for satisfactory washing. Indeed, a washing agent containingbetween 0.25 and 5.0 parts by Weight of high-titre soap per 100 parts ofsolution gives excellent results very economically. Preferably, theagent contains between 0.5 and 2.5 parts of high-titre soap dissolved in100 parts of softened water. However, other surface-active washingagents with equivalent or similar detergent properties may be employed,with or without added alkali. Conveniently, a small quantity of glacialacetic acid may be added to the agent for the purpose of maintaining theconcentrated solution liquid at room temperatures in order to facilitateits handling. The temperature of the agent, unlike that of the washingliquor, has little effect on the efficacy of washing, but a temperatureof 60 C. has been found to be convenient.

Particularly in conjunction with the preferred washing agent referred toabove, a preferred washing liquor consists of an alkaline solution withan alkalinity of about 1 to 1.25 gms. per litre net of equivalent freesodium carbonate, for example 0.25 part by weight of sodium metasilicate(Na SiO 5H O) in 100 parts of soft water at a temperature of 822 C.,giving a pH value of about 11.8. Other similar, widely used, alkalis maybe employed, such as caustic soda or trisodium phosphate (Na PO 12H O).If another alkali is used, the quantity required and the equivalentgrains per gallon of free sodium carbonate can be determined from thefigures quoted above in proportion to the chemical equivalent of thealkali used.

The washing agent and/or the washing liquor may, if required, have anaddition of an artificial soil-suspending agent, such as polyvinylpyrrolidone, sodium carboxymethyl cellulose or sodium carboxymethylstarch or other chemicals used in orthodox washing processes to enhancethe suspending power and prevent redeposition of dirt on the materialduring rinsing stages.

In an alternative form of process in accordance with the invention,alkali and detergent or soap are mixed together in the requiredproportions and are applied together as the washing agent. In this case,the washing liquor may be a more dilute alkaline solution or even softwater without alkali. The washing agent may be a solution containing ahigh-titre soap in a concentrated form, between 0.25% and 2.5% by weightand an alkali such as a sodium metasilicate, between 0.25% and 2.5%dissolved in soft water. Preferred concentrations are between 0.4% and1% of high-titre soap and between 0.4% and 1% of sodium metasilicate.Soil-suspending agents may again be added to either or both components.

Also in accordance with the invention, a machine for the washing,cleansing or like treatment of textile articles, fabrics, fibres or likematerials comprises at least one stage with means for applying asurface-active washing agent to the material, and at least one stagewith means, separate from and independent of the aforesaid means, forapplying a washing liquor to the material with an energy level not lessthan times that with which the said washing agent is applied.

Means may be provided for carrying the material through the said stagesin the form of a continuously moving web or between continuously movingliquid-pervious carrier webs.

The washing agent may be applied by spraying, as described above, or bypassing the material over one or more troughs containing the agent, thelevel in the or each trough being kept constant and the material beingcontrollably depressed as it passes thereover. With more than onetrough, the material may be caused to enter the liquid in a secondtrough only when additional washing agent requires to be applied.

Means for removing surplus washing agent may comprise a pair of rolls,controllably loaded one against the other, between which the material ispassed.

An alternative means for applying and removing the washing agent and/orrinsing liquor may comprise a pair of rolls controllably loaded oneagainst the other, between which the material is passed, the rollshaving their axes in a common plane substantially departing from thevertical and the space between the upper surfaces of two rolls beingcontrollably flooded with the said agent or liquor.

For washing individual flat articles in a continuous series, the washingagent may be arranged to be automatically applied only whilst an articleis directly passing the point of application, the applying means beingautomatically shut off and prevented from feeding further quantities ofthe agent when a gap between successive articles occurs.

Examples of apparatus for carrying out the process of the invention willnow be more fully described with reference to the accompanyingdiagrammatic drawings, in which:

FIGURES l and 2 illustrate two machines for laundering separate'articles,

FIGURES 3 to 5 alternative ways of applying a washing agent,

FIGURE 6 a machine for processing a continuous length of material orfabric, and

FIGURE 7 a machine for processing textile fibres in bulk.

In a machine for laundering separate articles, as illustrated in FIGURE1 or FIGURE 2, the articles are carried through the machine between anupper belt 10 and a lower belt 11, both of a net-like structure. Thearticles are placed in succession on top of the belt 11 at point A andare removed from the machine at point B (FIGURE 1). The path of the belt10 coincides with that of the belt 11 between A and B, where the beltsdiverge, the belt 10 returning above and the belt 11 below the machinearound a series of guide rolls 12 and over tensioning rolls 13 loadedthrough a controllable linkage, such as levers 14, by pneumaticcylinders or springs 15, so that the belts are kept under constanttension.

Between A and B, the belts 10, 11 are driven by pairs of rolls 16, 17loaded against each other by pressure applying means, such as cylindersor springs 18 (FIG- URE l). The rolls are driven from an electric motor19 through chains and sprockets 20. The speed of the driving means ispreferably variable to suit the requirements of the particular articlesor material being treated.

C and D represent one washing stage and E and F two rinsing stages.Between D and E, further washing stages similar to C and D may beincluded, if necessary, to deal with more heavily soiled articles or foroperating at higher speeds.

Within a single washing stage, two distinct and separate operations arecarried out, firstly a surface-active washing agent is applied to thearticles at C and secondly washing liquor is used at D to apply energyto the articles and remove the soiling. Suitable washing agents andliquors have been described above. In the machine of FIGURE 1, theapplication of the washing agent is carried out as follows: A tank 21 isfilled with a highconcentrate washing agent supplied through a pipe andlevel controller 22 from a convenient external source. A circulatingpump 23 takes solution from the tank and passes it through a filter 24and control valve at 25 to a manifold 26 fitted with distribution pointsor nozzles 27. The manifold 26 extends transversely of the direction ofmotion of the belts 10, 11 as they pass from a roll 'pair G to a rollpair H. The manifold 26 is adjusted about its axis so that the washingagent, which is evenly spread by spraying across the full width of thearticles, comes into contact with them at such an angle and velocitythat there is little agitation of the agent and a low energy elfect, asdiscussed above, at the point of contact. The valve at 25, adjustablefrom a remote-control panel 28, allows the operator to vary the pressureat which the agent is delivered to the manifold 26 and hence the volumeof agent delivered to the articles.

The belts 10, 11, on passing through the rolls 16, 17 at G are heldclosely in contact with each other with the articles between them.Beyond the point of application of the washing agent, they pass throughthe rolls 16, 17 at H, where the said agent is brought into intimatecontact with the individual fibres of the articles, air being excludedby the pressure of the rolls. As the amount of agent which passesthrough the rolls with the articles is determined by the thickness ofthe articles and the pressure, means for varying the pressure betweenthe rolls 16, 17 at H is provided on the panel 28.

Excess washing agent is squeezed out of the articles as they passthrough the rolls at H and is collected in the tank 21 forrecirculation. The top of the tank is provided with a lip 29 which comesinto close proximity with the bottom of the roll 16 to prevent suchagent from being carried into a wash-liquor tank 50.

As regards stage C, the machine of FIG. 2 differs from FIG. 1 in thatthe articles are carried through the washing agent in the tank 21 ashereinafter more fully described.

FIGURE 3 illustrates an alternative distributing arrangement forapplying the washing agent in which the manifold 26 is so directed thatthe agent makes contact with the surface of the roll 17 at G and notdirectly with an article. The rotation of the roll spreads the agentevenly and carries a proportion of it over to its front, where it entersthe article before the latter passes through the roll pair at G. Afterthe article has passed through this roll pair, remaining washing agentdrops from the back of the roll 17 onto the article and passes with itto the roll pair at H. The tank 21 is fitted with an extension 30 underthe roll pair at G to collect washing agent expressed from the articlesby the action of the pair.

FIGURES 4a and 4b and FIGURES 4c and 4d illustrate two arrangements inwhich the washing agent is applied only whilst an article is passing theapplication point and its delivery is stopped when no article is passingor when an article passing does not require the application of aparticular agent available at that stage. In FIGURES 4a and 4c, thearrangements are shown in the positions in which no washing agent isapplied and in FIGURES 4b and 4d in the positions in which the agent isapplied. In both arrangements, the agent is supplied through a pipe 31to a level-controller which allows the agent to fill a trough 32 to apreset level controllable from the panel 28. A detecting device 33,which may conveniently be a photo-sensitive electric device, is arrangedto sense the passage of an article 34 which requires the application ofthe agent. When this device operates, it produces a signal which,through a time-delay device 35, causes a cylinder 36, conveniently apneumatic cylinder, to be supplied with pressure. In the arrangement ofFIGURES 4a and 4b, the piston of the cylinder 36 causes a roller 37,supported by a lever 38 from a bracket 39, to descend and depress thebelts 10, 11 together with the articles 34 into the trough 32 and belowthe levelof the agent therein (FIGURE 4b). As the belts and article passthrough the trough, they pick up washing agent from the trough, but thelevel controller causes the level to be maintained. After the delaydevice 35 has operated, the cylinder 36 or a restoring spring returnsthe roller 37 to the position of FIGURE 4a, in which the belts 10, 11pass over the trough 32 without entering it, so that no agent isapplied.

In FIGURES 4c and 4d, the devices 33 and 35 act in a similar manner, butthe piston of the cylinder 36 acts directly on the trough 32, causing itto tilt about a pivot 40 until it is in contact with a stop 41 (FIGURE4d). In this position, the washing agent in the trough 32 flows over aweir 43 and down an extension 44 onto the belts 10, 11 passingunderneath at L. In the inoperative position (FIGURE 40), the trough isin contact with a stop 42.

In FIGURE 5, which shows both a side elevation and a detail view atright angles thereto, the two rolls 16, 17 at G are mounted with thecommon plane containing their axes tilted substantially from thevertical. A V- shaped reservoir for washing agent thus formed betweenthe two rolls and end plates 47 is supplied by a pipe andlevel-controller 46. The belts 10, 11 travelling between the rolls passthrough the washing agent and only a limited quantity of agent,controlled by the pressure between the rolls, is carried along with thearticle. The level in the reservoir is maintained so that the agent, fedin towards the mid length of the rolls, flows outwardly towards and overthe end plates 47. Any dirty washing agent which has been squeezed outfrom the articles by the rolls 16, 17 and has passed over the plates 47is carried away through a pipe 48 and filtered before being returned tothe tank 21 for recirculation.

After the belts 10, 11 have passed with an article through the roll pairat H (FIGURE 1), so that the article contains an amount of washing agentwhich has been brought into intimate contact with the fibres, the

said belts carry the article on towards a roll pair I (FIG- URE 1 or 2).In the section D, between H and I, the acticle is subjected to theaction of a washing liquor with a high energy effect, as discussedabove. In FIGURE 1, below the belts 10, 11, the wash-liquor tank 50contains a heating means, such as a steam coil 51, by which the liquoris kept at a predetermined temperature controlled by atemperature-sensitive valve 52. Liquor is taken from the bottom of thetank 50 by a pump 53 and passed through a filter 54 to manifolds 55 and56 mounted, respectively, above and below the belts 10, 11 and arrangedto deliver liquor through the said belts. Because of the net-likestructure of the belts, the liquor will strike the articles with littleinterference from the belts. The liquor is distributed from themanifolds 55, 56 across the full width of the belts by spreading meanssuch as nozzles 57 which give a series of fan shaped spray jets.

At this stage, the washing agent in an article has been utilised to rollup dirt and grease on internal and external surfaces of the fibres andis holding this soil in suspension. The washing liquor, with the energyit imparts to the article, assists the agent to remove the soil from thestructure of the material of the article and carries away the said agentand soil in suspension together with any unaffected agent and falls downfor collection in the tank 50, filtering and re-circulation.

Washing liquor remaining in the article is reduced to a minimum by thepressure in the roll pair at I, the expressed liquor being alsocollected in the tank 50, which has an extension 58 for this purpose.Dirt which accumulates in the tank 50 is removed partly by the action ofthe filter 54 and partly by an amount of liquor carried away from thesurface through a drain 59 and from the bottom of the tank through adrain 60. As liquor is thus removed, the level in the tank is maintainedby clean water carried over from an adjacent wash stage or rinse stagethrough an inlet 61. The entry of this water tends to reduce theconcentration of alkalinity or other chemical additives in the washingliquor and this concentration is made up to the required strength byconcentrate supplied through an inlet 62 under the control of a valveactuated by an alkalinity detector 6 3.

Baflles 64, 65 are fitted above the section D to ensure that no washingagent passes unintentionally from C to D and that no washing liquorpasses from D to a following wash stage or to a rinse stage E.

The articles then proceed to further stages between the belts 10, 11. InFIGURE 1, rinsing stages E and F comprise tanks 66 and 67 containingrinse liquors. The belts 10, 11 carry the articles over a guide roll 68down into liquor in the tank 66 and, following a path determined byguide rolls 69, 70 and 71, to a pressure-loaded roll pair I. Remaining,soiled, washing liquor is diluted by the rinsing liquor and removed bythe action of this roll pair. The rinsing action is assisted by themovement of the belts through the liquor and may be further assisted byvibrating means such as mechanical or ultrasonic beaters. The section Fis similar to the section E. Fresh water fed into it through a pipe '72flows through the machine in a direction counter to the movement of thebelts 10, 11 into the section B and thence into the washing stages. Inthe tanks 66 and '67, weirs may be fitted to ensure that this flow isnot 'broken up by local reverse currents in the tanks. Heaters such as asteam coil 73 are incorporated to maintain the liquor at a requiredtemperature.

Additional operations such as bleaching and starching, and/ or theaddition of fiuorescing or other additives may be provided for, ifrequired.

After passing through a roll pair 16, 17 at K, the upper belt is carriedaway, while the articles remain on the lower belt 11 until they aretransferred to a calendar or ironing machines.

The pumps '23, 53, motor 19, rollers 16, 17, in bearings such as 74(FIG. 5), together with other mechanical components are mounted on aframe 1, which may be subdivided. Covers 2 and 3 enclose the machine andprevent splashing. Internal covers at 4 protect the return path of thelower belt 11.

The machine of which a part is shown in FIGURE 2 may be generallysimilar to that of FIGURE 1. The belts 10, 11 with articles between thempass through the roll pair at G and then around a guide roll 75 intoconcentrated washing agent in the tank 21 and around further guide rolls76 and 77 to the roll pair at H. In passing through the tank 21, thearticles absorb washing agent and excess agent is removed by the rollpair at H. EX- pressed surplus agent is collected in a trough 78 fromwhich it passes through a filter and separator 79. Filtered agent isreturned to the tank 21 through a pipe 80 and separated dirt isdischarged through a pipe 81. The amount of washing agent in the tank 21is maintained by a level controller at 22.

Washing liquor is applied in the section D. After passing through theroll pair at H, the belts 10, 11, with articles held between them, passaround guide rolls 82, 83, '84 and to the roll pair at I. In so doing,the belts pass bet-ween manifolds 86 and 87 and manifolds 87 and 88supplied by the pump 53. The manifolds are arranged so that the washingliquor strikes the articles energetically whilst they are travelling ina substantially vertical path before and after they pass through theliquor in the tank 50.

In addition to or instead of the spraying action of the manifolds, thebelts 10, 11 may pass through agitating means such as pairs of beaterbars 89. The bars 89 are mounted between two rods 90 which arereciprocated, for example, by a crank 91 pivoted at 92 and connected toan eccentric driver by the motor 19. The vibration and agitationproduced by the bars 89 assist the washing liquor in removing finelydivided soil particles from the articles. The action of the bars may beaugmented or complemented by energy produced by an ultrasonic generator93. This energy is transmitted in the form of high-frequency vibrationsthrough the liquor to the articles immersed therein. If the energy isapplied through the liquor from the bars 89 without the manifolds 86-88being used, the pump 53 may operate at low pressure to circulate liquorthrough the filter 54 and back to the tank 50. From the roll pair at I,the belts 10, 11 pass to one or more rinsing stages or first to furtherWashing stages.

Preferably the belts 10, 11 used, as described above, as carriers forseparate articles are webs of net-like structure made from filaments ofartificial fibre by warp knitting or weaving so as to produce an evenmesh. The structure is selected to ensure minimum interference with theaction of the washing liquor, whilst permitting the greatest possibleexpression of moisture from the articles during their passage betweenpressure-applying rolls. A mesh of approximately four threads percentimetre in each direction is suitableQThe net-like structure may bereinforced along each edge to cooperate with known webguiding andcontrolling mechanism. Advantageously, the woven or knitted material ispreset by known heat finishing or resin finishing to give a stablestructure capable of withstanding continuous cycles of washing, rinsing,mangling and drying Without deterioration.

The machine of FIGURE 6 is also generally similar to that of FIGURE 1,but is especially intended for the treatment of continuous orsemi-continuous lengths of fabrics or textile materials. As there are noseparate articles, the belts 10, 11 of the previous figures are notessential. A roll of material 94 is mounted on a feeding stand 95 andone end is threaded, through sections C, D, D, E, F and G, to receivingstand 96, Where it is rerolled at 97. Washing agent supplied by pipe 22is applied at C and washing liquor at D and also D. Rinsing takes placeat E and F and drying or ironing at G. In the section C, where thearrangement is otherwise similar to that of FIGURE 2, the roll 76 may befitted with lifting means such as a cylinder 98, so that when washingagent does not require to be added, the roller 76 and the material canbe lifted above the level of the agent in the tank 21. The sections Dand B may each be generally similar to the section D of FIGURE 1.

The rinsing means in section F comprises manifolds 99, 100 which receivehot clean water from a supply at 103 and deliver it, as rinse liquor,directly to the material between the roll pairs at J and K. Surplusliquor expressed by the roll pair at K and collected in the tank 66 iscirculated thence by a pump 108 through a filter 107 to manifolds 101and 102 which deliver it to the material between the roll pairs at I'and J. The liquor expressed by the action of the roll pair I iscollected in a tray 104 which feeds it to the tank 50 of the section D.

An alternative form of rinsing section which could be used would besimilar to the arrangement of FIGURE 5, but the level controller 46would deliver rinse liquor instead of washing agent.

The section G comprises drying or ironing rollers 105 co-acting with arecessed bed 106.

A machine such as has been described with reference to FIGURE 6 may beadapted for the treatment of separate articles and, conversely, machineshaving the features described with reference to FIGURES 1 to may beadapted for the treatment of continuous lengths of material.

FIGURE 7 shows a machine for the processing of fibres or like bulkmaterials, such for example as the scouring of raw wool. The material109 is stored in a hopper 110 from the bottom of which a rotating comb111 delivers it to a belt 112 driven by rollers 113. Above the belt 112is a further, moving-link, belt 114 driven from rollers 115. Suspendedfrom the belt 114 are a series of combs 116 mounted so that they move inpositions substantially perpendicular to the surface of the belt 112,spreading the material evenly over the surface of the latter. At theupper end of the belt 112, the layer of material is fed onto the surfaceof the lower belt 11 which carries it forward under the upper belt 10.The belt compresses the material and holds it firmly in relation to thelower belt 11 during its passage through roll pairs G, H and the rest ofthe machine. The machine may otherwise be similar to a machine such ashas been described with reference to FIGURES 1, 2, 5 or 6. For thescouring of wool, however, it is generally necessary to use lowertemperatures than are permissible for laundering other materials. Ascompared with conventional wool scouring machines, the invention permitsof the use of a smaller'machine for the same output and result.

In the scouring of wool, the soil being removed is generally due tonatural soiling. In a number of processes for textile materials,however, treatment such as mercerizing, sizing or dyeing involve addingto the materials at one stage chemicals which have then to be removed ata later stage, either partly or completely. The process of the presentinvention is especially advantageous when applied to the removal of suchchemicals or other artificial soiling introduced during a priortreatment.

The invention is applicable with particular advantage to high-speedcontinuous processes and to c0ntinuousprocess machines such as have beendescribed above. However, it can also be applied to batch-processmachines.

I claim:

1. A continuous process for the washing of textile material in thepresence of a surfactant comprising,

as a first step applying the surfactant in a liquid medium to thesurface of the textile material and in intimate contact with the fibersthereof while the material is in an unwetted state, and

thereafter as a second distinct step applying a surfactant to thematerial with an energy level significantly greater than that employedin the first step.

2. The process of claim 1 in which the energy level of the applicationof the surfactant in the second step,

measured in terms of units of energy per unit of area of materialprocessed, is at least one hundred times as great as the energy level ofthe application of the surfactant in the first step.

3. The process of claim 1 in which the concentration of the active agentof the surfactant in the first washing step is at least times greaterthan the concentration of the active agent of the surfactant in thesecond washing step.

4. The proces of claim 1 in which the concentration of the active agentof the surfactant in the first washing step is at a level to provide adetergency effect equivalent to an aqueous solution of orthodoxhigh-titre soap in a concentration of between 0.25 and 5.0 parts byweight of active fatty-acid soap in parts of solution.

5. The process of claim 1 in which the concentration of the active agentof the surfactant in the second washing step is at a level to provide adetergency effect equivalent to an aqueous solution of orthodoxhigh-titre soap of less than 0.01 part by weight of active fatty-acidsoap in 100 parts of solution.

6. The process of claim 1 in which the concentration of the active agentof the surfactant in the first step is at a level to provide adetergency effect equivalent to an aqueous solution of orthodoxhigh-titre soap in a concentration of between 0.25 and 5.0 parts byweight of active fatty-acid soap in 100 parts of solution and in whichthe concentration of the active agent of the surfactant in the secondwashing step is at a level to provide a detergency effect equivalent toan aqueous solution of orthodox high-titre soap of less than 0.01 partby weight of active fatty-acid soap in 100 parts of solution.

7. A continuous process for the washing of textile material in thepresence of a surfactant comprising,

as a first step applying the surfactant in a liquid medium to thesurface of the material and in intimate contact with its fibers whilethe material is in an unwetted state,

thereafter applying as a second distinct step a surfactant to thematerial with a concentration of the active agent of less than that ofthe concentration of the active agent in the first washing step,

the concentration of the active agent in the first washing step beingmore than 50 times as high as the concentration of the active agent inthe second washing step.

8. The process of claim 7 in which the surfactant in the first washingstep is applied to the material with an energy level of less than 1.85times 10* joules per square centimeter of material.

9. The process of claim 7 wherein the surfactant is applied to thematerial in the second washing step with an energy level of more thantimes 10" joules per square centimeter of material.

10. The process of claim 7 wherein the surfactant is applied to thematerial during the first washing step with an energy level of less than1.85 times 10* joules per square centimeter of material and thesurfactant is applied to the material during the second washing stepwith an energy level of more than 185 times 10* joules per squarecentimeter of material.

11. The process of claim 7 wherein the surplus surfactant from the firstwashing step is removed from the textile material before it is subjectedto the second washing step.

References Cited UNITED STATES PATENTS MAYER WEINBLATT, Primary ExaminerU5. (:1. X.R. 8-458; 689, 43

